Often described as a kind of Pokémon for the age of blockchain, CryptoKitties has gained more than 1.5 million players since its debut in November 2017.

In a blog post announcing the investment, CryptoKitties said: "We envision a world of play, one without limits. Where ownership is real, and the things you create and discover, you can keep forever. Where games can be entire economies, unlocking mutual incentives for players and builders to extend the gaming experience. Where the world is built by everyone who chooses to be a part of it - especially you. The future is meow."